For the record, we're HUGE fans of Neil deGrasse Tyson. (You don't put someone on the cover of your magazine if you don't love him!) In our excitement, we dreamed up lots of cover executions, but ultimately, we decided the most fitting treatment would be to have him beaming from the center of the solar system. Here's hoping you like the interview as much as we do!

When he was 17, Neil deGrasse Tyson got a letter from Carl Sagan, the Cornell astronomer and popular science luminary. Tyson was a Bronx High School of Science student applying to colleges, and Sagan invited him for a tour of the lab at Cornell. It was “an act of generosity that has affected me my entire life,” Tyson says. A few years later, in 1980, Sagan launched Cosmos: A Personal Journey, a 13-part television series that explored heady subjects like black holes, extraterrestrial life, and the beginning of the universe. Sagan passed away in 1996, but the Cosmos project was intentionally left open-ended. Now Tyson, an astrophysicist who directs the American Museum of Natural History’s Hayden Planetarium, is set to pick up where Sagan left off with a new iteration of the series, Cosmos: A Space-Time Odyssey. Tyson recently spoke with mental_floss about his personal relationship with Sagan, time travel, and the theoretical possibility of an evil, mustache-less twin living in an alternate universe.

Not long ago, you tweeted that if we imagined our planet’s history as a football field, human existence would fit on a blade of grass.Yes. If the 14-billion-year history of Earth went from end zone to end zone, then the width across one blade of grass is about the time that has elapsed since the paintings of cavemen to this conversation. That’s a cosmic perspective.

How has the cosmic perspective shifted since the original Cosmos aired? What advances in science or new issues have you had to incorporate?If you go back 40 years, [the thinking about] the environment was “don’t pollute the lake because then you’ll kill the fish, and it will mess up our little water hole.” No one was thinking that what they did locally would affect everybody else globally. The local–global connection has emerged in the last couple of decades.

Some of that came about because of our understanding of how the dinosaurs went extinct. How could an asteroid hit one part of Earth and make something extinct on the opposite side?

The only way that can happen is if you catastrophically affect the climate. So climate change as a local force driving a global phenomenon has become a topic of discussion since the original Cosmos.

[At the time of] the original Cosmos, we knew of no planets beyond our solar system. We could hypothesize they’d be there, but now the list [of planets we know about] is rising. One thousand exoplanets! But Cosmos is not simply about “let’s teach you the latest science discoveries.” Then it would be just any other documentary. Its real contribution is that it shows how and why science matters.

I was reading a collection of Sagan’s Gifford Lectures, The Varieties of Scientific Experience, and he really did have a way with words. He was talking about our sun going supernova, and he said, “Some five or six or seven billion years from now, the sun will become a red giant star and will engulf the orbits of Mercury and Venus and probably Earth. Earth, then, would be inside the sun, and some of the problems that face us on this particular day will appear, by comparison, modest.” He has this implicit humor.There are plenty of smart people out there who don’t know science, and plenty of socialized people who might not be smart. He had all of that in the same package.

What was your relationship with Sagan like?We met only four times. So he was never a mentor. People think that, but that was not the case. But those four times were significant, so I think of him often, and they serve as a source of inspiration. The fact that he took the time for me [as a high school student] has shaped how I take time for students who reach out to me.

How did the new Cosmos come about?After he died, I got a phone call from the board at the Planetary Society, an organization that he cofounded, asking me to join the board. That was a little bittersweet, because clearly the spot was vacated because of Sagan’s death. It was that acceptance that got me closer to his widow, Ann Druyan, who was a cowriter of the original series and is the writer of the current series. This is 1997, I think, and the conversation about doing Cosmos and continuing the Cosmos legacy had always been there. The question was, “How would we do it? Who would write? Who would be in it?” And Ann might have had other people in mind, I don’t know, but I knew it was something I could do, possibly uniquely, given my sentiment for Carl and the impact he had on science literacy in the country. And given the rising impact that I was having at the time, I felt, yeah, I can do this.

So are there going to be shots of you walking by the beach with the breeze blowing through your hair?Afros don’t respond to breezes. [Like Sagan] I embrace any occasion to address a camera lens to tell people what’s going on. [But] the fact is, we have stunning visuals knitted into stories of how and why science matters. So I’m on camera only if it’s really adding to that delivery.

Somebody has to man the helm of the spaceship of the imagination.Yes. Those are some of the most fun scenes I filmed. The spaceship looks to the past, the present, and the future through portals in the ship. Of course, it’s all done with a green screen. But because I feel very close to the universe, when I’m describing what you’re seeing, even though I can’t see it, I can see it. In my head, it’s there. As we descend toward the sun’s surface, as we descend into strands of a DNA molecule, as we go to the limits of telescopic regions of the universe, I am there.

Seth MacFarlane, who is one of the producers of Cosmos, recently did an episode of his show Family Guy, where the dog, Brian, died but came back in some kind of time travel twist in space time. Were you consulted on that?When Brian died, it was tragic, and I thought, “Well it would be sad if he’s not there because he’s a unique voice in the program.” Stewie had the time machine already, right? So the show had already involved time travel, so [I thought] if they bring him back, they would probably just pull something out of the walls like that. There is one episode I was consulted on, unknown to me at the time. [Seth and I] had lunch, and he asked me 20 questions on the space-time continuum and multiverses. Six months later, there’s a show. Stewie takes the time machine, goes back to before the big bang, in fact goes outside of the big bang, where he is neither in a time nor a place, and it’s out of that fluctuation in his time machine that the universe gets started. And at the end, an entire title card says: science consultant, neil degrasse tyson. Anytime I’m with Seth, he’s asking me questions about science and the universe. He’s just a curious guy.

On the issue of parallel universes, do you think there is an evil mustache-less Neil deGrasse Tyson out there?No. I think you need more than an infinite number of universes in the multiverse to have a universe that has someone who is exactly like me but is evil.

And without a mustache.Usually, the evil person has a mustache. But my evil twin would have to be mustache-less, I suppose. When everything else is identical except that Neil is evil, I think we need more than an infinite number of universes for that. There are orders of infinity. Most people don’t know this. Some infinities are larger than others, so you can show mathematically that that’s the case. So I just think if you had infinite universes, that order of infinity is not high enough to create an Earth that has everything else exactly like it except that there’s an evil version of me.

So is space a human abstraction or a physical entity in your opinion?It’s our perception of reality limited to how our senses deliver it to us. It’s only in the era of science that we can decode the operations of nature outside of those five senses. And we’ve come to learn—since the era of quantum physics in the 1920s—that the results of your experiments are to be trusted above whatever your senses are telling you. Your senses are actually quite useless in this regard. They’re not only useless—they are actively misleading. So you design your experiments, and you trust the results of your experiments. I’m still going to operate based on the reality that my senses give me in my day-to-day life.

In 34 more years, if there was another installment of Cosmos, what questions would it address?Part of the mystery of science is not even knowing yet what question to ask. For example, in the year 1799, the question, “I wonder if an asteroid will ever strike us and render us extinct” could not have existed because we hadn’t discovered asteroids yet. And even after we did discover asteroids, the idea that maybe one would hit us was not a thought for another century and a half, until we figured out that the crater in Arizona, which then was known as Barringer Crater, is now known to be the product of an asteroid impact and quickly renamed it Meteor Crater. The fun part about the future is not even knowing what questions to ask.

Right, because five years from now, some alien empire could invade and change our understanding of everything. There’s no way to predict that.Exactly. And it will re-shift, and it will readjust how we pose questions. And what we pose questions about.

A few years ago, I sent 10 dollars into something called the Time Travel Fund, with the idea being that the interest accrues, and far into the future, they take that money and come back in time and save you before death. What do you think of that as a retirement plan?I think it’s great if it only costs you 10 dollars. Think of all the stuff you might spend 10 dollars on that wouldn’t be nearly as fun to think about as that. If anything, you get novelty value from it. Not enough of us embrace the value of novelty.

Cosmos premieres on Fox on March 9 and on The National Geographic Channel on March 10.

This story originally appeared in mental_floss magazine. Subscribe to our print edition here, and our iPad edition here.